There was a movie where a guy was living behind the walls in there house and watching them. Its not people under the stairs. This is one guy and I think he had some kind of secret passage way through the house. Maybe from the 80's or 90's.

Yep, I've seen this one. Could be;

Hider in the House (1989) (http://www.imdb.com/title/tt0097503/)

I think that is it thanks!

Also sounds like Bad Ronald! That's seventies though.